Prostatic Acid Phosphatase by Radioimmunoassay-Reply

In Reply.—  As suggested by Dr Klein and as we noted, clinical stage A and B cases often advance in stage when staged pathologically. Our assertion that the prostatic acid phosphatase radioimmunoassay could be a useful staging adjunct applies particularly to those clinical stage A and B cases that have an elevated serum level of acid phosphatase. Our experience, like Dr Klein's, suggests that such patients are likely to have more advanced disease than suspected clinically. Our study findings are consistent with this view in that none of the seven pathologically staged A and B cases had a positive test result. As we stated, because the pathological stages of the A and B cases with positive test results were not available to us, additional work is needed. For the present, a positive test occurring in a patient with apparent early stage disease should be viewed as an ominous sign, possibly